Process for the production of a photographic print

ABSTRACT

This invention relates to the rapid processing of photographic material. The development takes place in a solution which contains a 3-pyrazolidone compound, a hydroquinone and a development anti-foggant.

[ Oct. 1, 1974 1 PROCESS FOR THE PRODUCTION OF A PHOTOGRAPHIC PRINT [75]Inventors: Monica Hilary Gent; Brian George Sanderson, both of llford,England [73] Assignee: Ilford Limited, Ilford, Essex,

England [22] Filed: Oct. 12, 1972 [21] Appl. No.: 297,085

[52] US. Cl. 96/665, 96/66 HD [51] Int. Cl G03c 5/30 [58] Field ofSearch.. 96/50 PT, 66 R, 66.3, 66 HD,

[56] References Cited UNITED STATES PATENTS 3,397,987 8/1968 Luckey etal. 96/66.5

3,576,633 4/1971 Henn et al. 96/66.5 3,647,459 3/1972 Taber et al.3,718,469 2/1973 Hatano et al. 96/50 R OTHER PUBLICATIONS Mason,Photographic Processing Chemistry, 1966, pp. 3941, 153-154.

[5 7] ABSTRACT This invention relates to the rapid processing ofphotographic material. The development takes place in a solution whichcontains a 3-pyrazol1d0ne compound,

a hydroquinone and a development anti-foggant.

7 Claims, No Drawings PROCESS FOR THE PRODUCTION OF A PHOTOGRAPHIC PRINT1n the processing of most photographic print material of the silverhalide emulsion type, the material after an imagewise exposure, isdeveloped by immersion in a sil-,

I A substantial number of photographic prints are now i made fromphotographic material which comprises a silver halide emulsion coated ona base which consists of a paper sheet laminated on both sides to apolyethylene layer. lt is possible to process exposed photographicmaterial of this type which is hereinafter referred to a polyethylenelaminated photographic material relatively rapidly because processingsolutions cannot be absorbed by the paper base since they never comeinto contact with it. Thus the washing stage in the normal processingsequence may be shortened very greatly since it is required to removethe excess processing chemicals and processing reaction products onlyfrom the emulsion and not from paper base as well. Interest, therefore,has arisen in trying to reduce the time required for the remainder ofthe processing sequence when processing polyethylene laminatedphotographic material.

The greatest period of time spent by an operator in the processing ofpolyethylene laminated photographic material is the time spent waitingto visually examine the exposed material after immersion in thedeveloping solution. Photographic developing solutions have anappreciable induction period, that is to say to seconds elapse beforeany image appears on the print material after it has been immersed inthe developing solution. As soon as the image starts to appear itdevelops very rapidly so that within 1 or 2 seconds after its firstappearance the operator would be able to tell ifthe exposure time werecorrect and thus if the print is able to be used. This has theadvantages of reducing the time wasted if the print is incorrectlyexposed and of reducing the overall development time when correctlyexposed.

It is the object of the present invention to provide a process for theproduction of a photographic print using polyethylene laminatedphotographic material wherein the induction period in the developersolution is considerably reduced.

Therefore according to the present invention in a process for theproduction of a photographic print using polyethylene laminatedphotographic material of the silver halide emulsion type which comprisesthe sequential steps of imagewise exposing the material, developing thelatent silver image, fixing out the unexposed silver halide, washing thefixed material and drying the material there is provided the step ofdeveloping the exposed photographic material in a silver halidedeveloper solution which comprises from 0.5 to 2 g per litre of a3-pyrazolidone compound of the general formula. RIHC C=O wherein R is ahydrogen atom or a methyl group and R is a hydrogen atom or an alkyl oralkoxy group containing fromone to four carbon atoms, together withhydroquinone or a substituted hydroquinone developing agent, the ratioby weight of the hydroquinone or substituted hydroquinone to the3-pyrazolidinone compound being from 3 1 to 5 l and there being presentin the silver halide developing solution sufficient developmentanti-foggant to prevent-a properly exposed print from being fogged, thepH of the developer being 10.0 to 11.5.

The preferred 3-pyrazolidone is 1-phenyl-3- pyrazolidone. Examples ofsuitable substituted hydroquinones are chloro-hydroquinone and methylhydroquinone.

Any of the usual development anti-foggants may be used. However theymust be present at an appreciably higher concentration in the developersolution than the concentration present in most normal developingsolutions.

For example mercapto-tetrazole compounds which are well-known asdevelopment antifoggants may be used. Preferably the concentration ofthese compounds in the developer solution is within the range of 0.01 to0.1 g/litre. The preferred mercapto-tetrazole for use in the inventionis phenyl mercapto-tetrazole 7 Other w eTl-liiiown developmentantifoggant compounds which may be used are nitrobenzimidazoles, forexample 5-nitrobenzimidazole, nitroindazoles, for example6-nitroindazole and 5-nitroindazole, benzotriazole and derivatives ofbenzotriazole for example 5- methylbenzotriazole. Preferably theconcentration of these compounds in the developer solution is within therange of 0.05 to 0.5 g/litre. i I V The pH of the developer solution ofuse in the present invention is preferably 10.6, but can be within therange 10.0 to 11.5.

The developer solution of use in the present invention may contain inaddition the normal constituents of developing solutions, e.g.,sequestering agents, potassium bromide as a restrainer, antioxidantssuch as sodium sulphite. Water-miscible solvents e.g. ethylene glycolmonomethyl ether, to help dissolve the l-phenyl- 3-pyrazolidone, may bepresent when the developer is compounded as liquid concentrate and is tobe diluted 1 part plus 9 parts water for use. Concentrates for dilutionin the range 5 fold to 20 fold may also be prepared.

3-Pyrazolidone compounds of the formula hereinbefore set forth and inparticular l-phenyl-3-pyrazolidone have found great use as photographicdeveloping agents. However they are normally used in small amounts, e.g.from 0.05 to 0.2 grams per litre, together with relatively greateramounts of hydroquinone, e.g.

from 5 to 15 g/litre to form a synergistic developing solution. Whensynergistic developing solutions of this type are used the inductionperiod of print photographic material developed therein is about 20seconds. However when polyethylene laminated photographic material isdeveloped in the developing solution of the present invention theinduction period is reduced virtually to nothing. This is bothunexpected and very useful since it reduces very considerably the period required for the operator to have to wait in order to visuallyexamine the photographic material in the developing solution while theimage is developing. Further the process of the present inventionenables the development time required in the processing of eachpolyethylene laminated photographic print to be reduced by between 20seconds and 1 minute.

The following Example will serve to illustrate the invcntion.

EXAMPLE The following developing solution was compounded:

Sodium sulphite, anhydr. Hydroquinone Potassium carbonate l-phenyl-3-pyrazolidone Sodium hydroxide Potassium bromide Phenylmercapto tetrazole Ethylene diamine tetraacetic acid (disodium)Ethylencglycol monomethyl ether Water 0.15 g. l ml. to l litre Ammoniumthiosulphate (60% w/w solution) Boric acid Sodium hydroxide Sodiummetahisulphite Sodium sulphite. anhydrous Acetic acid. glacial WaterThen the material was washed for 1 minute in running cold water. Finallythe print was dried for 30 seconds in a hot air cabinet. A fullydeveloped dry print was obtained by this process after 3 minutes.

in another test using the same photographic material but wherein theformula of the developer used was:

Sodium sulphite. anhydrous Hydroquinone Potassium carbonatel-Phenyl-B-pyrazolidone Sodium hydroxide 0.55 Potassium bromide 0.5Benzotriazole 0.06

Water to l The induction period of the material in the developer beforeany image appeared was seconds and 120 seconds were required for fulldevelopment. Thereafter the material was fixed, washed and dried asbefore. A fully developed dried print was obtained after 4 /2 minutes.Thus by the process of the present invention an overall saving ofalittle more than 1 minute in the processing of a print was obtained.However 20 seconds of this is time which would have been spent by theoperator doing nothing but waiting to inspect the photographic materialin the developer.' The overall reduction in time is due to the greateractivity of the developer. Nevertheless, the total time of the materialin the developer is sufficiently long to enable the operator to obtainan acceptable print, e.g., removing it from the developer before the 1minute, if it has been overexposed.

We claim:

1. In a process for the production of a photographic print usingpolyethylene laminated photographic material having coated thereon atleast one silver halide emulsion layer which process comprises thesequential steps of imagewise exposing the material, developing thelatent silver image, fixing out the unexposed silver halide, washing thefixed material and drying the material the improvement which comprisesdeveloping the exposed photographic material in a silver halidedeveloper solution which comprises from 0.5 to 2 g per litre of a3-pyrazolidone compound of the formula wherein R is a hydrogen atom or amethyl group and R is a hydrogen atom or an alkyl or alkoxy groupcontaining from one to four carbon atoms, together with a hydroquinonedeveloping agent, the ratio by weight of the hydroquinone developingagent to the 3- pyrazolidinone compound being from 3 l to 5 1 and therebeing present in the silver halide developing solution sufficientdevelopment antifoggant to prevent a properly exposed print from beingfogged, the development anti-foggant being selected from the groupconsisting of a mercapto-tetrazole, a nitrobenzimidazole, anitroindazole and a benzotriazole, the pH of the developer being 11.0 toll.5.

2. A process according to claim 1 wherein the 3- pyrazolidinone isl-phenyl 3-pyrazolidinone.

3. A process according to claim 1 wherein the development anti-foggantcompound is a mercaptotetrazole compound.

4. A process according to claim 3 wherein the mercaptotetrazole compoundis pheny'l mercaptotetrazole.

5. A process according to claim 3 wherein the concentration of themercaptotetrazole compound in the developer is from 0.01 to 0.1 g/litre.

6. A process according to claim 1 wherein the development anti-foggantcompound is a nitrobenzimidazole, a nitroindazole, a benzotriazole or amethylbenzotriazole.

7. A process according to claim6 wherein the concentration of thedevelopment anti-foggant compound in the developer is from 0.05 to 0.5g/litre.

1. IN A PROCESS FOR THE PRODUCTIION OF A PHOTOGRAPHIC PRINT USINGPOLYETHYLENE LAMINATED PHOTOGRAPHIC MATERIAL HAVING COATED THEREON ATLEAST ONE SILVER HALIDE EMULSION LAYER WHICH PROCESS COMPRISES THESEQUENTIAL STEPS OF IMAGEWISE EXPOSING THE MATERIAL, DEVELOPING THELATENT SILVER IMAGE, FIXING OUT THE UNEXPOSED SILVER HALIDE, WASHING THEFIXED MATERIAL AND DRYING THE MATERIAL THE IMPROVEMENT WHICH COMPRISESDEVELOPING THE EXPOSED PHOTOGRAPHIC MATERIAL IN A SILVER HALIDEDEVELOPER SOLUTION WHICH COMPRISES FROM 0.5 TO 2 G PER LITRE OF A3PYRAZOLIDONE COMPOUND OF THE FORMULA
 2. A process according to claim 1wherein the 3-pyrazolidinone is 1-phenyl - 3-pyrazolidinone.
 3. Aprocess accordIng to claim 1 wherein the development anti-foggantcompound is a mercaptotetrazole compound.
 4. A process according toclaim 3 wherein the mercaptotetrazole compound is phenylmercaptotetrazole.
 5. A process according to claim 3 wherein theconcentration of the mercaptotetrazole compound in the developer is from0.01 to 0.1 g/litre.
 6. A process according to claim 1 wherein thedevelopment anti-foggant compound is a nitrobenzimidazole, anitroindazole, a benzotriazole or a methylbenzotriazole.
 7. A processaccording to claim 6 wherein the concentration of the developmentanti-foggant compound in the developer is from 0.05 to 0.5 g/litre.